Everything

The vampire may lengthen her tongue at will, splitting it into a fork like that of a serpent. The tongue may reach 18 inches or half a meter, and makes a ter-rifyingly effective weapon in close combat.

System: The lash of the tongue’s razor fork causes aggravated wounds (difficulty 6, Strength damage). If the Kindred wounds her enemy, she may drink blood from the target on the next turn as though she had sunk her fangs into the victim’s neck. Horrifying though it is, the tongue’s caress is very like the Kiss, and strikes mortal victims helpless with fear and ecstasy. Additionally, the tongue is highly sensitive to vibrations, enabling the vampire to function effectively in the darkness the Clan prefers. By flicking his tongue in and out of his mouth, the vampire can halve any penalties relating to darkness (p. 274).